People watching is a widespread practice among urbanites all over the world and although Berlin may not have the popular squares of Rome, it does have its share of sidewalks lined with cafés. When the weather permits, neighborhood cafés and bars appear to spontaneously expand onto the sidewalks. This allows for better people watching, but it also gives us the opportunity to enjoy the little sidewalk gardens that are springing up more and more frequently around the city. A number of business owners have taken it upon themselves to beautify their sidewalks by planting flowers in the small rectangular spaces of concrete-free earth that used to (and sometimes still do) house ornamental trees. On the other hand, some of these gardens have been created by guerilla gardeners who actively reclaim these abandoned spaces and turn them into beautiful, green oases. Lastly, a third type of sidewalk “garden” exists: these are the accidental gardens, which plants have inhabited all of their own accord. It is in this last space where we have recently come across a number of fascinating plants, several of which are members of the nightshade family (Solanaceae) and which have inspired us to do a series of posts on a few nightshade species that grow in Berlin.

Chinese lanterns (Physalis alkakengi), otherwise known as Bladder cherry, Winter cherry, Cape Gooseberry, or even “Love in a Cage,” makes a stunning contribution to the autumn colors that Berlin is beginning to display. However, its bright orange, bladder-shaped husk (calyx) is not purely ornamental; it also hides a perfectly round and equally colorful fruit in its center. This little “winter cherry” is edible when ripe and is filled with twice as much Vitamin C as lemons, but the unripe berry, along with all other parts of the plant, is poisonous (due to the same solanine found in tomato leaves and raw potatoes) so care must be taken when harvesting these fruits! The plant has a long history of herbal uses including anti-inflammatory, fever-reducing, and cough-suppressing treatments.

After coming across one of the above-mentioned “accidental gardens” which could barely contain all of the Chinese lanterns that had made their home there, we were instantly intrigued. The brightly-colored lanterns look similar to the Physalis fruits which can be bought in grocery stores throughout the city, so we decided to investigate further. Once we learned that the fruit was indeed edible, we immediately tasted them and decided they would be a great ingredient for homemade salsa. In fact, the sweet and slightly acidic undertones were complemented perfectly by the tomatoes, onions, and cilantro. See our recipe and photos on our Foraging Recipes page. Now we just need to figure out where we can buy some decent tortilla chips in Berlin!

A quick look at our plant map betrays our precise geographical preferences for urban foraging and nature observation. The still largely undeveloped no man’s land along the former Berlin wall provides a sanctuary for many wild plants that would otherwise be regimented to more formal landscape practices. These abandoned spaces serve an important function because their lack of landscape architecture helps disrupt the plant blindness often found in city dwellers. The familiar patterns of trees lining a street one after the other, neatly trimmed bushes and meticulously mulched flower beds are non-existent in these spaces; here, plants can no longer be confined to our peripheral vision as mere ornaments but, rather, take on a central role of their own.

It is in one such space, known as the “Nasses Dreieck,” where we found – next to a pile of concrete remnants of the former Berlin wall – a plant whose history is firmly intertwined with what the English speaking world regards as a quintessential German product, namely beer. You may have already heard of the “Reinheitsgebot” or German Beer Purity Law. The law came into effect in the early 16th century and it dictated the only permissible recipe for beer: the holy trinity of barley, water and hops.

The rise of Common hop (Humulus lupulus) from botanical obscurity coincides with the success of the plant’s female flower cluster in keeping beer from spoiling. Using tea made from hops was thought to have sedative powers since ancient times, but otherwise the plant seems to have had relatively little medicinal value compared with other plants. Before the introduction of hops in the beer brewing process, an herbal concoction known as grut (or gruit) was responsible for preserving the precious liquid. The Common hop’s fate as a species was sealed when it began being cultivated in Germany for brewing beer in the 11th century. After it became popular in the use of beer brewing, the plant was eagerly examined for other possible uses and health benefits, and continues to be researched even today; for more about the medicinal value of hops, see this recent article from the American Botanical Council.

The unusual configuration of hops twisting around a birch tree next to the railroad tracks, the large remnants of the Berlin Wall stacked into a haphazard pile, and the old, half-way destroyed sofa sitting next to them, all disrupt our automatic mode of urban vision that traditionally assigns plants a passive, ornamental role…. Here, we can actively reflect on the role of urban nature and the history of botanical species. The only thing missing from this experience is a nice pint of beer!

As you may have noticed, temperatures have lowered and humidity has increased due to the frequent rain we’ve been receiving lately. In Berlin this marks the onset of mushroom season, a time when cockeyed hordes of mycophiles descend in the woods around Brandenburg looking for tasty treats. However, this does not mean that the city itself is fungus-free: a common and strikingly beautiful dweller of Northern woodlands is also frequently found in Berlin.

Turkey Tail (Trametes versicolor) often colonizes decomposing pieces of wood and can be found (among other places) on large tree stumps in the city’s sidewalks. True to its Latin name, the mushroom comes in many colors, which, coupled with its undulating shape, makes for a mesmerizing spectacle. However, there is much more to this mushroom than meets the eye!

Turkey Tail has a long and esteemed history in traditional Chinese medicine and it is also one of the most medically researched mushrooms in the world. A compound isolated from the mushroom is used to boost the immune system in conjunction with regular cancer treatment. In particular, the mushroom has shown great promise in the treatment of breast and lung cancer. The mushroom is also edible although it is rather chewy and does not have much flavor. In alternative medicine, it is often prescribed in tea form for various illnesses. Finally, the versatile mushroom can also be used to dye fabrics or, alternately, fade their colors. Compounds from the mushroom are industrially used as an environmentally-conscious bleach to give jeans their “faded” look.

Although this mushroom is common, it is often mistaken for False Turkey Tail (Stereum ostria). To tell the two apart, it suffices to observe their undersides. False Turkey Tail completely lacks the pore surface of its lookalike. For a complete identification key, see here.

Most foragers are reluctant to try eating brightly colored berries belonging to plant species unknown to them; this type of skepticism is healthy and reinforced by the multitude of poisonous berries in nature. We had never seen a common sea-buckthorn (Hippophae rhamnoides) bush before and its bright orange clusters of berries appeared uninviting. Little did we know at the time that we were passing up on one of nature’s superfruits!

Sea-buckthorn is a deciduous shrub which is native to a large area of Asia and Northern Europe. In Asia the berries’ nutritional and medical properties have been known for millenia. The small, tart berries are packed with vitamins, minerals and antioxidants. Sea-buckthorn oil is known to absorb ultraviolet rays, and Russian astronauts used it as a sort of space sunscreen. Furthermore, many victims of the Chernobyl nuclear disaster were treated with sea-buckthorn against radiation burns and today many high-end cosmetic products contain sea-buckthorn as an anti-aging product.

Given that the berries’ properties verge on the miraculous, why aren’t the markets brimming with sea-buckthorn? To answer this question, we invite the reader to pick a few sea-buckthorn berries. You will immediately find out that the holy bush doesn’t easily give up its fruits. The berries cling tightly to the branches, which also happen to be covered with ferocious but camouflaged thorns. Hand harvesting sea-buckthorn is extremely labor intensive, and the only mechanization methods developed so far involve freezing the berries and shaking the branches (which also damages the plant itself). Still, in Germany the plant has received a lot of attention since the 1940’s and, in particular, was the subject of a lot of scientific research in former East Germany. A liqueur made from sea-buckthorn is considered a North German specialty.

Sea-buckthorn is not widespread in Berlin.* Mundraub.org marks one located near the Mauerpark (close to the outdoor climbing wall north of the park). The shrubs are actually on private property and only a few branches hang over the fence with berries on them. You are better off trying out another nearby location which is a public space (and which we’ve marked on our map)!

*Now that our eyes are more accustomed to recognizing sea-buckthorn shrubs, we’ve discovered that they do, in fact, grow throughout Berlin! However, they tend to be tucked away in less trampled-upon spaces where they can better protect their fruit from foragers. Today we saw several shrubs next to the Bornholmer Strasse S-Bahn station, but unfortunately their branches had been cut and the plants were severely damaged. This was quite sad to see and is a strong reminder that there is a delicate line between respectfully foraging and greedily harming a plant for its fruit!

Last week we were walking along Cantianstrasse in Prenzlauerberg when we suddenly noticed some strange-looking hazelnut husks on the ground. Sure enough, upon closer inspection the husks contained what appeared to be smallish hazelnuts. Since no self-respecting forager could pass on this opportunity without letting his tastebuds settle the matter, we cracked open a few nuts and crunched them to oblivion. The taste was mild but distinctive enough to confirm our suspicions: we were eating hazelnuts! We looked around and saw no shrubs or bushes, only a few tall trees whose canopies were difficult to observe in the dim evening light. After returning home, we did some research and confirmed the identity of our suspect, the Turkish Hazel (Corylus colurna) tree.

Turkish Hazel is the largest species of hazel, reaching well over 20 meters with a stout, long trunk and branches that form a pyramidal shape. The nuts were introduced to Western Europe in the late 16th century from Constantinople. In recent times it has gained popularity among landscape architects and city planners because it is highly resistant to disease and pests, and tolerant of urban environments. The very characteristics that make Turkish Hazel an excellent tree for urban environments also make it suitable for large scale grafting onto the smaller, yet more well-known Common Hazel (Corylus avellina). Although Common Hazel has nuts that are slightly larger and have a stronger flavor, they also have a tendency to sucker and are susceptible to the disease known as Eastern Filbert Blight. Grafting the Common Hazel onto the Turkish Hazel eliminates these problems. Still, after snacking on Turkish Hazel nuts for a few days, we firmly believe they have culinary merit of their own.

Yesterday and today, we went back to look for more Turkish Hazel trees and were suprised to find them all over our area in Prenzlauerberg. The trees essentially line the southern side of Kopenhagenerstrasse, and are found in many nearby streets. The nuts are littering the sidewalks, and besides a few frustrated pigeons that keep picking up the nuts without being able to crack them, nobody is paying any attention to them. As a matter of fact, we often witnessed large piles of husks and nuts that were swept in street corners destined for landfills. This kind of wastefulness is astonishing, given the supposed German penchant for frugality!

To remedy this, we harvested a good amount of the Turkish Hazelnuts we found and came up with an original recipe for Turkish Hazelnut Pesto!

P.S. As we were outside shelling our foraged Turkish hazelnuts (a rather time-consuming task!), some children from the neighborhood curiously came over to see what we were doing. When their mother saw us, she asked if we had found these hazelnuts by the kindergarten down the street. Since we were not aware of any hazelnut trees in our vicinity, we immediately went to check it out and, sure enough, we found a Common Hazel leaning over the sidewalk in front of the school! We picked up a few of the hazelnuts that had fallen onto the sidewalk and quickly did a size and taste comparison. Surpisingly, we found that we actually preferred the taste of the Turkish Hazelnuts (longer harvesting workload aside)! Below are a couple of images to show the difference between the two different nuts and their husks.

The process of integration in Germany, much like the rest of Europe, can be a slow one. Today we briefly focus on a botanical immigrant to Berlin – the Staghorn Sumac (Rhus typhina). The plant was introduced to Europe in the early 17th century. After making its way to Germany, it remained for much of the next two centuries an exotica worthy only of botanical gardens and few other green spaces. (The widespread cultivation of the plant did not begin until the middle of the 20thcentury.) Staghorn Sumac is a deciduous small tree that is native to eastern North America. At home in the swampy regions of the Appalachians Mountains but also in Southeastern Canada, the plant is no stranger to colder climates. Coupled with an ability to sprout easily and grow rapidly even in poor soil, Staghorn Sumac seems to weather Berlin’s continental climate quite well. The fruit of the plant forms red clusters of drupes which are found at the end of branches. Native Americans soaked the fruit in water to make a refreshing type of lemonade , a tradition which is carried out today by adventurous outdoorsmen and curious foragers. The fruits’ sour properties are reflected in its German common name Essigbaum, which literally translates as “Vinegar Tree.”

A large number of Germans have been unknowingly enjoying the dried ground fruits of Tanner’s Sumac (Rhus coriaria) for a couple of decades via Middle Eastern and North African spice mixtures (called Za’atar). Next time you order a Döner Kebab, sumac will likely be part of your meal. From a culinary perspective, the integration of sumac is nothing short of a success story.

The deep-hued red fruits of the Sumac remain throughout the year and provide a welcome contrast to the colourless Berlin winters. The specimen identified in our photographs (Rhus typhina) can be found along Bornholmer Strasse between Bergener and Bjoernson Strasse. However, it is on private property so you’ll need to ask permission or find another one if you want to make sumac lemonade! The photographs of sumac lemonade featured below were taken a few summers ago in Virginia, where Staghorn Sumac is plentiful and grows freely.